#!-interpreted #!-interpreters work on Linux, but not BSD (macOS). A #!/usr/bin/env shim works portably—but fails inside a Nix build, whereas a full Nix path breaks the kernel's 127-char #!-line limit on Gitlab CI's Docker runner. Software: it's kluges all the way down.
Counting chars as if it mattered... Linux's way of making me feel younger... Prediction: in the future, accelerated em's will be code bummers, because digital computers will be as subjectively slow to them as in the early days of computing.
Read my blog!